Latest news with #solarSystem
Yahoo
a day ago
- General
- Yahoo
Scientists found a possible new dwarf planet — it could spell bad news for Planet 9 fans
When you buy through links on our articles, Future and its syndication partners may earn a commission. A potential new dwarf planet has been discovered in the outer reaches of the solar system, and its existence poses the greatest challenge yet to the hypothesis that a ninth planet lurks far from the sun. "We were very excited to discover 2017 OF201 because it was not expected at all," study leader Sihao Cheng of the Institute for Advanced Study in Princeton, told "It's very rare to discover an object both large and with an exotic orbit." "The object's aphelion — the farthest point on the orbit from the sun – is more than 1,600 times that of the Earth's orbit," Cheng explained in a statement. "Meanwhile its perihelion — the closest point on its orbit to the sun — is 44.5 times that of the Earth's orbit, similar to Pluto's orbit." We're learning more and more about the outer solar system. Beyond Neptune is the Kuiper Belt; a ring of icy cometary nuclei and planetesimals dominated by Pluto and Charon. The Kuiper Belt begins about 30 astronomical units (AU) from the sun (one AU is the distance of Earth from the sun), its inner edge guarded by Neptune, and extends out to 50 AU. NASA's New Horizons spacecraft is currently exploring the Kuiper Belt. Meanwhile, the twin Voyager spacecraft have already sped through the Kuiper Belt and have entered a realm called the Scattered Disk, which is thought to go all through way out to more than 1,000 AU and is home to icy bodies on highly elongated and highly inclined orbits. These objects were literally scattered in the region through gravitational interactions with Neptune, and have had their orbits further modified via torques induced by the gravity of passing stars, or the "galactic tide" (the overall gravitational field of the Milky Way galaxy). Beyond the Scattered Disk is the Oort Cloud, which is an immense volume of space that possibly stretches up to a light-year from the sun and is the source of long-period comets. However, much about the Scattered Disk is still unknown, and besides those long-period comets that venture this way every now and then, no Oort Cloud object has ever been seen — they are too far away and too small. This is why every discovery of a trans-Neptunian object (TNO) on a greatly elongated orbit is vital for piecing together the mystery of the outer solar system. Around 5,000 TNOs have been discovered until now, but the latest discovery may be one of the most important. Known as 2017 OF201, it is currently 90.5 AU away from the sun, but its orbit brings it as close as 4.14 billion miles (6.66 billion kilometers) from our star and as far away as a whopping 157 billion miles (244 billion kilometers). from the sun. For the vast majority of its 24,256-year orbit, 2017 OF201 is too far away to be seen with current telescopes; it could only be discovered because its last perihelion came in 1930, and that it's still relatively close. The object's last perihelion also came, coincidentally, during the same year that Clyde Tombaugh discovered Pluto with a 13-inch (330mm) telescope at Lowell Observatory in Arizona. Would it have been possible for Tombaugh to have also found 2017 OF201? Probably not — at magnitude +20.1, this object would have been four magnitudes fainter than Pluto, and it is even fainter today. Fortunately, telescopic technology has come a long way in the past 95 years, with deep surveys that can capture the passage of a faint object. For example, the Dark Energy Survey (DES) has identified about 800 TNOs — and that's even though DES is ostensibly a cosmological survey. In the same vein, Cheng, along with Jiaxuan Li and Eritas Yang of Princeton University, have been scrutinizing observations made by the Dark Energy Camera Legacy Survey (DECaLS) on the Victor M. Blanco 13-foot (4-meter) telescope at the Cerro Tololo Inter-American Observatory in Chile. They discovered 2017 OF201 in archive data going back to 2017 from DECaLS, and also spotted it in old data dating from 2011–12 captured by the 11.7-foot) (3.58-meter) Canada–France–Hawaii Telescope on Mauna Kea. Based on its brightness and its expected albedo of 0.15 (meaning it would reflect just 15% of the sunlight incident upon it), Cheng's team calculated that 2017 OF201 is probably about 435 miles (700 kilometers)) across. This would make it the second largest object found on such an elongated orbit. Although it is substantially smaller than Pluto, which is 1,477 miles (2,377 km) across, 2017 OF201 is nevertheless large enough to be classified as a dwarf planet. However, 2017 OF201's existence contradicts the Planet Nine hypothesis, based on our best guess as to Planet Nine's orbit. Planet Nine is a concept that was introduced in 2016 by Caltech astronomers Michael Brown and Konstantin Batygin to explain a perceived clustering of the orbits of many extreme TNOs. The gravity of Planet Nine, which is speculated to be a super-Earth or modest ice giant, would be influencing the orbits of extreme TNOs — or so the hypothesis goes. Yet, the orbit of 2017 OF201 is not clustered with the others. "Many extreme TNOs have orbits that appear to cluster in specific orientations, but 2017 OF201 deviates from this," Jiaxuan Li said in the statement. In our e-mail interview with Cheng, he laid out the repercussions that this could have for the existence of Planet Nine's orbit. "Planet Nine does allow for extreme TNOs to have unclustered orbits, but those orbits are not stable," he said. The timescale in which Planet Nine would render 2017 OF201's orbit unstable, and kick it out of the solar system, is in the region of 100 million years. However, the process of placing 2017 OF201 in its current orbit, through gravitational interactions with Neptune that pushed 2017 OF201 out of the Kuiper Belt — followed by nudges from the galactic tide — takes billions of years. It's possible that 2017 OF201 has only recently arrived in its current orbit, which would mean Planet Nine might not have had time to disrupt its orbit yet. "One important thing is to see if the orbit of our object is stable," Cheng said. "I think, based on analytical criteria, our object is at the boundary between stable and unstable, so further investigation with more comprehensive simulations is needed to definitively rule out the Planet Nine hypothesis." Related Stories: — Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart — Hubble Telescope discovers a new '3-body problem' puzzle among Kuiper Belt asteroids — 2nd Kuiper Belt? Our solar system may be much larger than thought Intriguingly, 2017 OF201 is probably not alone in the outer solar system. It's purely by chance that it happens to be close enough to be detectable — for 99% of its 24,256-year orbit it is too far away to be seen. "2017 OF201 spends only 1% of its orbital time close enough to us to be detectable," said Cheng. "The presence of this single object suggests that there could be another hundred or so other objects with similar orbits and size; they are just too far away to be detectable now. Just think of that: There could be hundreds of dwarf planets in the outermost reaches of the solar system. "Even though advances in telescopes have enabled us to explore distant parts of the universe, there is still a great deal to discover about our own solar system," said Cheng. A pre-print of a paper describing the discovery is available on arXiv.
RNZ News
2 days ago
- General
- RNZ News
Possible new dwarf planet spotted near the edge of the solar system
By Will Dunham , Reuters An artist's impression of Planet Nine. Photo: Caltech Scientists have identified an object about 700km wide inhabiting the frigid outer reaches of our solar system that might qualify as a dwarf planet, spotting it as it travels on a highly elongated orbital path around the sun. The researchers called it one of the most distant visible objects in our solar system and said its existence indicates that a vast expanse of space beyond the outermost planet Neptune and a region called the Kuiper Belt may not be deserted, as long thought. The Kuiper Belt is populated by numerous icy bodies. Given the name 2017 OF201, the object falls into a category called trans-Neptunian objects that orbit the sun at a distance beyond that of Neptune. The object takes about 25,000 years to complete a single orbit of the sun, compared to 365 days for Earth to do so. The researchers said 2017 OF201 was identified in observations by telescopes in Chile and Hawaii spanning seven years. "It is potentially large enough to qualify as a dwarf planet. Its orbit is very wide and eccentric, which means it experienced an interesting orbital migration path in the past," said astrophysicist Sihao Cheng of the Institute for Advanced Study in Princeton, New Jersey, who led the study with collaborators Jiaxuan Li and Eritas Yang, graduate students at Princeton University. Its size is estimated to be a bit smaller than Ceres, which is the smallest of the solar system's five recognised dwarf planets and has a diameter of about 950km. Pluto, the largest of those dwarf planets, has a diameter of about 2377km. The mass of 2017 OF201 is estimated to be about 20,000 times smaller than Earth's and 50 times smaller than Pluto's. "We don't know the shape yet. Unfortunately, it is too far away and it is a bit difficult to resolve it with telescopes," Cheng said. "Its composition is totally unknown yet, but likely similar to other icy bodies." The discovery was announced by the Minor Planet Center of the International Astronomical Union, an international organisation of astronomers, and detailed in a study posted on the open-access research site arXiv. The study has not yet been peer-reviewed. Earth's orbital distance from the sun is called an astronomical unit. 2017 OF201 is currently located at a distance of 90.5 astronomical units from the sun, meaning 90.5 times as far as Earth. But at its furthest point during its orbit, 2017 OF201 is more than 1,600 astronomical units from the sun, while the closest point on its orbit is about 45 astronomical units. That means it sometimes is closer to the sun than Pluto, whose orbital distance ranges from 30 to 49 astronomical units as it travels an elliptical path around the sun. The researchers suspect that the extreme orbit of 2017 OF201 may have been caused by a long-ago close encounter with the gravitational influence of a giant planet. "We still don't know much about the solar system far away because currently, it is difficult to directly see things beyond about 150 astronomical units," Cheng said. "The presence of this single object suggests that there could be another hundred or so other objects with similar orbit and size. They are just too far away to be detectable right now." The five dwarf planets recognised by the International Astronomical Union are, in order of distance from the sun: Ceres, which is the largest object in the asteroid belt between Mars and Jupiter, then Pluto, Haumea, Makemake and Eris, which all orbit beyond Neptune. The organisation defines a planet and a dwarf planet differently. A planet must orbit its host star - in our case the sun - and must be mostly round and sufficiently large that its gravitational strength clears away any other objects of similar size near its orbit. A dwarf planet must orbit the sun and be mostly round but it has not cleared its orbit of other objects. Cheng said the discovery of 2017 OF201 has implications for hypotheses involving the potential existence of a ninth planet in our solar system, dubbed Planet X or Planet Nine. This is because 2017 OF201's orbit does not follow the pattern exhibited by other known trans-Neptunian objects, which tend to cluster together. Some scientists had hypothesized that such clustering was caused by the gravity of a yet-to-be-discovered planet. -Reuters
Gizmodo
3 days ago
- Science
- Gizmodo
The Strange Secret Behind Venus' Pancake Volcanoes
Venus is home to some of the weirdest volcanoes in the solar system—massive, flattened domes that look like planetary pancakes left to cool on the world's blistering surface. Scientists have long suspected these 'pancake domes' formed from thick, slow-moving lava. But a new study suggests that Venus' bendy crust may be crucial to the formation of the circular mounts. The research, published earlier this month in Journal of Geophysical Research: Planets, focused on one particularly enormous dome, Narina Tholus, which stretches nearly 90 miles (145 kilometers) across. Using old radar data from NASA's 1990s Magellan mission, researchers built a virtual model of the dome and tested what kind of lava—and what kind of crust—could produce such a geological flapjack. Turns out, lava alone doesn't explain the domes' strange shape. 'Our models show that flexure influences dome shape,' the researchers wrote, 'in the presence of more flexure, dome tops become flatter and sides steeper.' Just like the skin of more fleshy things, Venus' crust can dimple and deform when saddled with thick lava. When researchers simulated lava flowing over a bendy lithosphere, the molten rock stopped spreading and piled up, forming flat tops with steep sides—just like Venus' pancake domes. Crucially, this model also reproduced the crustal bulges spotted around some domes in previous studies. Still, not just any lava would do. Only ultra-dense lava—more than twice the density of water and over a trillion times as viscous as ketchup, as reported by Live Science, matched both the dome shape and the surrounding deformation. The researchers think such lava could take 'up to hundreds of thousands of Earth-years' to fully settle into these colossal structures. The team's model is based on just one dome, so it's not conclusive. But upcoming missions like NASA's VERITAS or DAVINCI will provide better topographic data to test their theory across more of Venus' thousands of volcanic features. Better understanding these features could yield more insights into the formation of the hellish planet, sometimes referred to as Earth's evil twin for the way its planetary evolution split off from the timeline that made our world wet, verdant, and rife with life.
CBS News
3 days ago
- General
- CBS News
Search for elusive "Planet Nine" takes surprising twist, astronomers say
It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it. Some astronomers say the strange, clustered orbits of icy rocks beyond Neptune indicate that something big is out there, which they have dubbed "Planet Nine." Now, a U.S.-based trio hunting the elusive world has instead stumbled on what appears to be a new dwarf planet in the solar system's outer reaches. And the existence of the new kid on the block could challenge the Planet Nine theory, the researchers have calculated. Named 2017 OF201, the new object is roughly 430 miles across, according to a preprint study, which has not been peer-reviewed and was published online last week. That makes it three times smaller than Pluto. An extraordinary dwarf planet discovered at the edge of our solar system @the_IAS — Tech Explorist (@TechExplorist) May 24, 2025 But that is still big enough to be considered a dwarf planet, lead study author Sihao Cheng of New Jersey's Institute for Advanced Study told AFP. "Lucky" discovery The object is currently three times farther away from Earth than Neptune. Its extremely elongated orbit swings out more than 1,600 times the distance between the Earth and the Sun, taking it into the ring of icy rocks around the solar system called the Oort cloud. It goes so far out, it could have passed by stars other than our sun in the past, Cheng said. During its 25,000-year orbit, the object is only close enough to Earth to be observed around 0.5 percent of the time, which is roughly a century. "It's already getting fainter and fainter," Cheng said. Artist rendering of what Planet Nine might look like CBS News The discovery suggests "there are many hundreds of similar things on similar orbits" in the Kuiper Belt beyond Neptune, Cheng said. After taking a risk spending more than half a year sorting through a difficult dataset in search of Planet Nine, Cheng said he was "lucky" to have found anything at all. The researchers are requesting time to point the James Webb, Hubble and ALMA telescopes at their discovery. But Sam Deen, a 23-year-old amateur astronomer from California, has already been able to track the dwarf planet candidate through old datasets. "OF201 is, in my opinion, probably one of the most interesting discoveries in the outer solar system in the last decade," Deen told AFP. "See almost to the edge of the universe" The icy rocks discovered in the Kuiper belt tend to have a clustered orbit going in a particular direction. Two decades ago, astronomers proposed this was due to the gravitational pull of a world up to 10 times larger than Earth, naming it Planet Nine and kicking off a debate that has rumbled since. It is also sometimes called Planet X, a name proposed for a hypothetical world beyond Neptune more than a century ago. Back in 1930, astronomers were searching for Planet X when they discovered Pluto, which became our solar system's ninth planet. But Pluto turned out to be too tiny — it is smaller than the moon — and was demoted to dwarf planet status in 2006. There are now four other officially recognized dwarf planets, and Cheng believes 2017 OF201 could join their ranks. When the researchers modeled its orbit, they found it did not follow the clustered trend of similar objects. This could pose a problem for the Planet Nine theory, but Cheng emphasized more data is needed. Samantha Lawler of Canada's University of Regina told AFP that this "great discovery" and others like it mean that "the original argument for Planet Nine is getting weaker and weaker." The Vera Rubin Observatory, which is scheduled to go online in Chile this year, is expected to shed light on this mystery, one way or another. Deen said it was discouraging that no sign of Planet Nine has been found so far, but with Vera Rubin "on the horizon I don't think we'll have to wonder about its existence for much longer." For Cheng, he still hopes that this huge planet is out there somewhere. "We're in an era when big telescopes can see almost to the edge of the universe," he said. But what is in our "backyard" still largely remains unknown, he added. Cheng made the discovery alongside colleagues Jiaxuan Li and Eritas Yang from Princeton University, and Li said the newly found object demonstrates the power of open science. "All the data we used to identify and characterize this object are archival data that are available to anyone, not only professional astronomers," Li said in a statement. "This means that groundbreaking discoveries aren't limited to those with access to the world's largest telescopes. Any researcher, student, or even citizen scientist with the right tools and knowledge could have made this discovery, highlighting the value of sharing scientific resources." The new discovery was officially announced by the International Astronomical Union's Minor Planet Center on May 21.
South China Morning Post
4 days ago
- General
- South China Morning Post
Hunt for elusive ‘Planet Nine' at edge of solar system offers surprise
It is an evocative idea that has long bedevilled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it. Some astronomers say the strange, clustered orbits of icy rocks beyond Neptune indicate that something big is out there, which they have dubbed Planet Nine. Now, a US-based trio hunting this elusive world has instead stumbled on what appears to be a new dwarf planet in the solar system's outer reaches. And the existence of this new kid on the block could challenge the Planet Nine theory, the researchers have calculated. Named 2017 OF201, the new object is roughly 700km (430 miles) across according to a preprint study, which has not been peer-reviewed, published online last week. That makes it three times smaller than Pluto.
